JPH06196930A - Gunn diode oscillator - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a Gunn diode oscillator in which a resonator is set to an optimum size to improve oscillation efficiency. A waveguide having a rectangular cross-section, a second electrode protruding into the waveguide, a first diode fixed to the waveguide and grounded, and a gun diode, A disc-shaped conductor made of a conductor that is disposed in the waveguide on the diode at a predetermined height from the inner wall surface on the Gunn diode side and is connected to the second electrode and that radiates a signal wave of a predetermined frequency by driving power. And a driving power supply means for penetrating the inner wall surface of the waveguide facing the inner wall surface and supplying the driving power, the diameter of the resonator being 0.45 of the waveguide wavelength. It is set to be not less than twice and not more than 0.55 times, and the predetermined height is set to be not less than 0.45 times and not more than 0.55 times the inner height of the waveguide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waveguide type Gunn diode oscillator using a Gunn diode which oscillates, for example, a millimeter wave band.

[0002]

2. Description of the Related Art Heretofore, this type of Gunn diode oscillator has a waveguide having a rectangular cross section for propagating a millimeter wave, and GaAs or In fixed to the waveguide and having one electrode grounded.
A Gunn diode made of P, a resonator for contacting the other electrode of the Gunn diode and radiating a millimeter wave to the waveguide, and a bias post for supplying a driving current to the Gunn diode via the resonator. It consists of and.

[0003]

In the Gunn diode oscillator constructed as described above, since the oscillation efficiency greatly varies depending on the size of the resonator, the size of the resonator greatly affects the oscillation performance. In the past, the optimum dimensions of this resonator have not been clarified, and therefore
When a resonator having an unsuitable size is used, there is a possibility that the oscillation performance may be deteriorated.

The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to provide a Gunn diode oscillator in which the resonator is set to an optimum size to improve the oscillation efficiency. That is.

[0005]

In order to achieve the above object, a feature of the present invention is to provide a waveguide having a rectangular cross section,
A Gunn diode having a second electrode protruding into the waveguide, the first electrode being fixed to the waveguide and being grounded, and a Gundiode on the Gunn diode on the side of the Gunn diode. A disk-shaped resonator, which is arranged at a predetermined height from a wall surface and is connected to the second electrode, and which is made of a conductor that radiates a signal wave of a predetermined frequency by driving power, and a waveguide facing the inner wall surface. A driving power supply unit that penetrates the inner wall surface of the tube and supplies the driving power, the diameter of the resonator is set to 0.45 times or more and 0.55 times or less of the waveguide wavelength, and The predetermined height is set to 0.45 times or more and 0.55 times or less of the inner height of the waveguide.

[0006]

According to the above-mentioned structure, the diameter of the resonator and the height from the inner wall surface of the waveguide in which the resonator is arranged are specified, paying attention to the fact that the size of the resonator greatly affects the oscillation performance. Range (resonator diameter; 0.45 times the wavelength of the waveguide or more, 0.
55 times or less, and the height is 0.4 of the inner height of the waveguide.
Since it is set to 5 times or more and 0.55 times or less), matching between the resonator and the waveguide is achieved, and the Gunn diode can be oscillated under optimum conditions.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view of a Gunn diode oscillator according to an embodiment of the present invention.

This Gunn diode oscillator is for oscillating in the W band (75 to 110 GHz) and has an inner width C = 2.
It has a hollow waveguide 1 having a rectangular sectional shape of 54 mm and an internal height D = 1.27 mm. The Gunn diode 2 is fixed to the bottom wall surface of the waveguide 1 by a mounting fixing portion 2b. One electrode (first electrode) is grounded via the mounting and fixing portion 2b. The distance from the tip of the electrode 2a in the Gunn diode 2 to the bottom surface of the inner wall of the waveguide 1 is set to about 0.40 mm. Here, the operating part of the Gunn diode 2 is made of InP, and oscillates a fundamental wave in the millimeter wave band of about 90 GHz during oscillation.

On the other hand, the waveguide 1 is provided with a branch pipe 3 penetrating the upper wall of the waveguide at a substantially right angle, and a metal bias for supplying electric power to the Gunn diode 2 is provided in the branch pipe 3. Post 4 is inserted. At the portion where the bias post 4 projects into the waveguide 1, a protrusion 5 having a length B is formed at the tip.
A disk-shaped resonator 6 having a thickness of about 0.3 mm (0.25 × D) is attached. The resonator 6 is made of brass and has a surface plated with gold. And
The length of the protrusion 5 is adjusted so that the tip of the bias post 4 is brought into contact with the second electrode 2a of the Gunn diode 2.

In this embodiment, the resonator 6 has a diameter A of 1.8.
˜2.0 mm (λ / 2, λ; free space wavelength), and the length B of the protrusion 5 is set to 0.2 to 0.3 mm. This is a numerical value determined based on a measurement experiment described later, and the length B of the protrusion 5 is 0.2 to 0.
By setting it to 3 mm, the distance H from the lower surface of the resonator 6 to the bottom surface of the inner wall of the waveguide 1 is 0.5 to 0.8 mm (D
/ About 2). As a result, the resonator 6 and the waveguide 1 are matched with each other, and the Gunn diode 2 can be oscillated under optimum conditions.

In the Gunn diode oscillator configured as described above, when a drive current is supplied from the bias post 4 side to the Gunn diode 2 through the electrode 2a, the Gunn diode 2 oscillates and the resonator 6 emits a millimeter wave. It radiates into the waveguide 1. As a result, the millimeter wave band signal wave propagates in the waveguide 1 and is sent to the outside.

The waveguide wavelength λg at this time is obtained by the following equation.

Λg = λ / √ (1- (λ / 2C) ² ) where C: inner width of waveguide (length on long side) 2C: wavelength corresponding to cutoff frequency of waveguide λ: Free space wavelength Next, a measurement experiment for determining the diameter A of the resonator 6 and the length B of the protrusion 5 will be described.

In this embodiment, paying attention to the fact that the size of the resonator 6 has a great influence on the oscillation performance, and in order to make the Gunn diode 2 oscillate under optimum conditions, the resonator 6 is based on the following measurement experiment. The diameter A and the length B of the protrusion 5 are determined.

That is, the operating voltage of the Gunn diode 2 is kept constant at 4.3 V, and the diameter A of the resonator 6 and the length B of the protrusion 5 are changed at intervals of 0.1 mm. To measure. The length B of the protrusion 5
FIG. 2 shows the relationship between the diameter A of the resonator 6 and the oscillation output when the value A is fixed to 0.2 mm and the diameter A of the resonator 6 is changed. Further, FIG. 3 shows the relationship between the length B of the protrusion 5 and the oscillation output when the diameter A of the resonator 6 is fixed to 2.0 mm and the length B of the protrusion 5 is changed. As shown in FIG. 2, when the length B of the protrusion 5 is fixed to 0.2 mm and the diameter A of the resonator 6 is changed to 1.6 to 2.2 mm, the diameter A of the resonator 6 is Oscillation output is 90 at 2.0 mm
It is the maximum of mW.

On the other hand, as shown in FIG. 3, the diameter A of the resonator 6 is fixed to 2.0 mm, and the length B of the protrusion 5 is 0.1 to 0.1 mm.
When the length is changed to 0.4 mm, the length B of the protrusion 5 is 0.3 mm, and the oscillation output is 94 mW, which is the maximum.

From the above measurement results, the combination of the diameter A of the resonator 6 and the length B of the protruding portion 5 that maximizes the oscillation output is as follows: It can be seen that the length B = 0.3 mm.

The diameter A of the resonator at which this oscillation output becomes maximum
The combination of the length and the length B of the protrusion varies slightly depending on the Gunn diode. For example, the diameter A of the resonator is A = 1.8 m.
In some cases, the maximum length is m and the length B of the protrusion is 0.2 mm. In consideration of this point, in the present embodiment, the dimension of the resonator 6 that maximizes the oscillation efficiency is set to the diameter A of the resonator 6 = 1.8 to
The length B is set to 2.0 mm and the length B of the protrusion 5 is set to 0.2 to 0.3 mm.

[0019]

As described above, according to the present invention, a waveguide having a rectangular cross section and a second waveguide in the waveguide.
Of the gun diode, the first electrode of which is fixed to the waveguide and which is grounded, and the inside of the waveguide on the gun diode at a predetermined height from the inner wall surface on the side of the gun diode. A disk-shaped resonator, which is arranged and connected to the second electrode, and which is made of a conductor that radiates a signal wave of a predetermined frequency by drive power, and a waveguide inner wall surface facing the inner wall surface. Drive power supply means for supplying the drive power, the diameter of the resonator is set to 0.45 times or more and 0.55 times or less of a waveguide wavelength,
And the predetermined height is 0.4 of the inner height of the waveguide.
Since it is set to 5 times or more and 0.55 times or less, the Gunn diode can be oscillated under optimum conditions, and the oscillation efficiency is improved.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a Gunn diode oscillator according to an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a diameter of a resonator and an oscillation output.

FIG. 3 is a diagram showing a relationship between a length of a protrusion and an oscillation output.

[Explanation of symbols]

 1 Waveguide 2 Gunn diode 2a Electrode 4 Bias post 5 Protrusion 6 Resonator

Claims (1)

[Claims] 1. A waveguide having a rectangular cross section, a Gunn diode fixed to the wall surface of the waveguide and having a first electrode connected thereto, and a Gunn diode on the Gunn diode on the side of the Gunn diode. A disk-shaped resonator, which is arranged at a predetermined height from the inner wall surface and is connected to the second electrode of the Gunn diode, and which is composed of a conductor that radiates a signal wave of a predetermined frequency by driving power, A driving power supply means that is provided to penetrate the inner wall surface of the waveguide opposite to each other and supplies the driving power, wherein the resonator has a diameter of 0.45 times or more the wavelength of the waveguide,
The Gunn diode is set to 0.55 times or less, and the predetermined height is set to 0.45 times or more and 0.55 times or less of an inner height of the waveguide. Oscillator.